Salivary IgA and serum IgA and IgG antibodies to crude gliadin and alpha-gliadin were measured in adult patients with untreated celiac disease, ulcerative colitis, Crohn's disease and normal controls. Antibody levels in saliva and serum in untreated celiac disease were significantly higher than in other groups. Alpha-gliadin antibodies appeared to be a better discriminator for serum but not for saliva. The assay of salivary IgA antibodies to gliadin offers a non-invasive test which would be particularly useful in the investigation of celiac disease and for monitoring compliance with a gluten-free diet.